Traffic marker



1,640,830 Aug. .30, 1927. A R. HUNT TRAFFIC MARKER Filed Oct. 18. 1924figure INVENTOR.

A TTORNE Y.

Patented Aug. 30, 1927 UNITED STA Annx n. HUNT, or SAN rnancrsco,cennromzm.

TRAFFIC MARKER.

Applicatlonflled October 18,.1924. Serial No. 744,365.

This invention relates to improvements in trafiic markers and moreparticularly to means for. imbedding permanent legends and directions instreet pavements, for the direction and control of traflic.

Among the objects of the invention are to provide a tile or block ofsuitable shape, that can be embedded in the plastic body of bituminous,cementitious and other forms of plastic pavement, or set in brick, woodblock or other forms of block pavement.

Another object is to so shape the marker block that it will not sinkbelow the surface of plastic pavements, when same be-.

come softened by summer heat.

A further object is to form the marker of such material and of suchnature that the exposed surface will preserve the necessary legibility,tractive surface and durability, so that the plane of the pavementsurface will be maintained under stress of traflic.

Other objects and advantages will appear as this description progresses.

In this specification and the annexed one sheet of drawings, theinvention is illustrated in the form considered to be the best but it isto be understood that the invention is not limited to such form, becauseit may be embodied in other forms and it is also to be understood thatin and by the claims following the description, it is desired to coverthe invention in whatsoever form it may be embodied.

In the drawings:

Fig. 1 is a perspective view of a section of pavement having a trafficmarker embedded therein in accordance with this invention.

.Fig. 2 is a side view of a marker block made in accordance with thisinvention.

Fig. 3 is a perspective from below of the same.

Fig. 4.- is an assembly view of a pair of blocks set in plasticpavement, shown in cross section.

In detail the construction shown in the drawings includes the markerblock, preferably having the square top surface 1, extending down to thelower edge 2, in lines perpendicular to the said top surface, see Fi 2.

' The restricted portion 3, is formed by the cylindrical curvesextending backwardly from the edges 2. These curves slightly under cutor extend above the plane of the edges 2, to form a tapered edgeextending downwardly at this point. These curves extend upwardly thendownwardly from the edges 2, then outwardly toward the shoulders 4, onthe four. sides of the block. See Fig. 3.

From the shoulders 4, the sides converge to the point 5,'giving the formof an inverted pyramid. The depth of the blocks may be equal to thedepth of the bituminous layer X, so that the oints 5 rest upon theunderlying base of the pavement-not shown. This precaution is rarelynecessary, since the scientific form of the block will prevent itsinking into the bituminous mass. and rectangular forms, like bricks arenot practical, because they continue to sink below the surface when thepavement becomes plastic under summer heat.

The color or tone of the marker blocks is chosen with re ard to the lowheat conductivity, preferably white or gray, with the idea of reflectingheat rays, whereby the impinging and surrounding bituminous mass ismaintained at a slightly lower temperature, which further aids insupporting the blocks.

The material for forming the blocks is preferably a vitreous clay of thenature of paving brick material, or any other material having therequisite characteristics of form, density, color, tractive efiiciencyand durability as set forth.

Fig. 4 illustrates two blocks set in the plastic pavement, with abuttinglateral edges, for the purpose of spelling any desired legend in thesurface of the pavement. The surrounding bituminous surface may bedepended upon for proper contrasting color to the tint or white of themarker block. A square white surface as in Fig. 1, may be laid-with theStop or other legend in red or other contrasting color. v

For convenience the marker blocks are assembled by gluing or cementingthe top surface 1, to a sheet of heavy paper, in the desired design, aspracticed in the mosaic art.

In its application to old pavements, the necessary area is removed fromthe bituminous top layer, or the same is softened by the application ofheat; the assembled marker blocks on the sheet of paper is set inposition with the points 5, downward. The blocks are then forced intothe plastic Experience has shown that cubicalmass of the pavement by theWei ht of a This particular. form is intended also to counteract thetendency of the blocks to topple over under the lateral stress of thetractive effort of vehicle passing thereover. Having thus described thisinvention what I claim and desire to secure by Letters Patent is: t

.1. A paving block having an overhanging top with perpendicular sides; acurved portion extending backward from said sides and upward above thelower edge of said top; and (a pyramidal 'b'ase tapering from saidcurved portion to a oint.

2. A paving block having an overhanging top with perpendicular sides; acurved portion extending backwardl from said sldes and terminating in ashoulder spaced downwardly beneath the bottom of said top; and apyramidal base tapering downwardly from said shoulder.

3. A paving block having an overhanging top with perpendicular sides; acurved portion extending backwardly from said sides then forwardly andterminating in a shoulder to form a restricted portion between said topand shoulder; and a pyramidal base tapering to a point from saidshoulder.

In testimony whereof I have hereunto fixed my signature.

ALEX R. HUNT.

